The present invention is directed to a five-way valve and, in particular, to a system and method employing the five-way valve for the transport of particulate matter
In a commercial power generating station, fly ash transport is typically managed by a system which comprises a fly ash hopper, a metering container for measuring the amount of fly ash to be transported, a first valve for regulating the movement of fly ash between the hopper and the metering container, a transport line for transporting fly ash out of the metering container, a second valve for regulating the movement of fly ash between the metering container and the transport line, and a five-way, triple diaphragm operated valve for regulating venting and pressurization of the metering container.
This five-way, triple diaphragm operated valve has many drawbacks. For example, the five-way, triple diaphragm valve has over two dozen crit1cal and maintenance intensive parts and thus frequently requires expensive and time-consuming maintenance. In addition, the valve can only be replaced if the fly ash transport system is shut down for safety precautions. Replacement time (not including the time necessary to also inspect and repair the valve) is on the order of two to four man hours. Replacement also requires disconnecting five joints in order to remove the entire valve from the transport system. The five-way, valve is also undependable because usually within six months after installation the ash transport system experiences slower ash transfer, and after one year the valve must be replaced.
Accordingly, there is a need for a system and method for managing the transport of fly ash which is highly reliable and easy to maintain.